JPH0513356B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an upper main wall and a lower main wall each having three side walls, and two main walls located in a plane-parallel relationship.
a substantially rectangular two-part housing, an outer cover and an inner cover having an opening along the front side through which the magnetic tape is fed from the reel; opening and closing the opening; The present invention relates to a magnetic tape cassette comprising a pivotally mounted front cover which covers the magnetic tape in the closed position of the front flap. Preferably, a locking mechanism is provided to prevent the lid from being opened if the lid is not intended to be opened. The cassette of the invention is suitable for magnetic recording and reproducing devices, such as video recorders, for example.

Previously known tape cassettes for video recorders have a tape guide that is open to the front in the lower part of the cassette and has a recessed area behind it. When introducing the cassette into the opening of the video recorder, the tape guide is introduced into this area. In order to protect from the outside,
These cassettes have a pivoting front lid that partially or completely covers the front surface of the cassette. However, because of the recess, the cassette is not completely protected from dust during operation, and dust accumulates on the tape, resulting in so-called signal interruptions. In modern tape cassettes, this recess is still located below the cassette when the cassette is loaded into a video recorder, but when not in use the tape can be placed between the front lid, which consists of an inner and outer cover. The tape is protected by a firm grip in the closed position. Therefore, it is possible to prevent dust from adhering to the tape and from damaging the tape. A cassette of this type and its front cover mechanism are described, for example, in DE 32 23 279 and DE 33 02 392. The front lid is attached to the left and right hand ends of the bottom side wall of the cassette and is adapted for vertical pivoting by means of two holes that include a hole on the side wall of the front lid. Two pins are engaged. A torsion spring on one side of this pin can be used to move the front flap vertically or push it counterclockwise. One end of the spring rests on a peg in the front side wall, and the other end rests on a protrusion in the upper side wall of the cassette (see German Patent Application No. 33 02 392). (See Figures 5 and 6). In the applicant's German patent application No. P33311609-53 dated August 22, 1983:
Use a torsion spring on the lid to bias the lid. The spring has a bracket arm that rests in a slot in the front end of the top of the cassette. Installing this type of cassette not only simplifies assembly, but also ensures that the front flap is secured during pivoting movements in the narrow space between the front lid and the upper front edge of the cassette. can be prevented. This type of cassette also has a lid locking mechanism to prevent the flap from opening when closed. Locking mechanisms of this type are described, for example, in DE 31 50 317 and 3 223 279. In this first specification, the front lid is opened from the outside by a spring-loaded locking element with a nose. In the second specification, the housing of the cassette includes, in the region of its lateral ends, a leaf spring element with a safety catch made of plastic, which catches when the front flap is in the closed position. It is designed to fit into the intended hole. When the lid is opened, the protrusion of the cassette retainer presses against the leaf spring member, allowing the safety catch to be moved away from the locking hole until it is released. Furthermore, cassettes, especially video
A locking mechanism for the cassette has been proposed.
This mechanism is located at the front of the lower side wall of the cassette.
It has a bearing that directs a lock bar with two arms, the arms being at a 45° angle to each other. The lock bar is rotatably supported by a bearing. The arm of the lock bar is supported by a nose on its free end facing towards the front lid. On the corresponding inner sides of the front lid there are locking elements behind which the noses of the arms of the locking bar engage when the front flap is in the closed position. A spring is used to shift the safety catch, thereby applying pressure from the rear wall of the safety catch or from the wall opposite the top of the cassette. This shifting spring can be, for example, the second arm of a torsion spring used to shift the front lid.

Front lid locking elements of known design have the disadvantage that they require very expensive auxiliary mounting devices for assembly and that the locking action on the front lid is incomplete.

In order to overcome this drawback, according to the invention, an upper main wall and a lower main wall each having three side walls and a front side where the magnetic tape coming from two reels positioned in plane-parallel relationship are fed. a substantially rectangular two-part housing having an opening along the side; and a pivoting front lid that partially covers the side wall and opens and closes the opening; , comprising outer and inner covers covering the magnetic tape in the closed position, the front lid being locked in the closed position by a lock bar, the lock bar being movable rearwardly and forwardly and extending below the cassette. located on one side of the part,
In a magnetic tape cassette for a magnetic recording and reproducing device, the locking bar has a first arm that interacts with a pin of the front lid, and is positioned at an acute angle to the first arm and interacts with the starting member. a second operative arm, the locking bar extending beyond the bearing journal, the extending arm locking the upper portion of the rearwardly located cassette in the closed position of the front lid; A U-shaped leaf spring is arranged between the rear wall of the support of the lock bar and the arm of the lock bar adjacent thereto, and acts as a stop against the wall of the lock bar. A magnetic tape cassette is provided which is characterized in that:

The present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 shows three side walls 4a, 4b, 5, respectively.
1 shows a magnetic tape cassette of the type described above, consisting of an upper part 1 and a lower part 2, comprising an upper main wall 4 and a lower main wall 3 having a, 5b, 6a, 6b.
Two tape reels are housed within the cassette in parallel plane relationship, between which the magnetic tape is passed along the front of the cassette housing and wound and rewound. The arrangement of the tape reel and the magnetic tape in the cassette is shown in detail in FIGS. 5 and 6 of DE 32 23 279 A1. At the front of the cassette there is a side member 10 having an outer cover 8 and an inner cover 9 (FIG. 2) and partially covering the side walls of the cassette housing.
A front cover 7 is provided having a and 10b.
When the front lid 7 is closed, the magnetic tape is sealed between the two covers and protected from possible damage. There are two holes 11 in the front left and right sections of the top of the cassette in FIG. This pivot pin 12 is installed in the hole 11 so that the front cover 7 can pivot. In order to properly displace the front cover 7, a helical spring 13 with one arm is used, which spring 13 rests on at least one of the pivot pins 12, for example. This spring 13 is mounted in a very simple manner by bending its inner end 14 round and inserting it into a slot 15 in the swivel bearing pin. The arms 16 of the bracket of this helical spring 13 extend along the interior of the lateral portions of the front cover 7 into the interior of the outer cover. The individual parts of the cassette, namely the front cover 7 and the upper part 2 of the cassette.
When assembling the helical spring 13 automatically positions itself in the groove 17 on the outside of the upper part of the cassette, thereby forcing the front lid into the closing position.

Behind the side parts 10b of the front lid 7 and on the corresponding side of the lower part 2 of the cassette, a support for the locking element of the front lid is arranged, which has a conventional U-shaped shape. Includes heavy side walls 18. The locking member of the front lid consists of two arms 20 (20a, 20b), 21 that are at an angle of about 45 degrees to each other.
Lock bar 19 comprising (21a, 21b)
It consists of The locking bar 19 is pivotably mounted in a bearing journal 22, which is inserted into a bearing 30 installed in the wall of the lower part 2. A locking pin 23 is installed on the side of the lateral portion 10b of the front cover 7 to limit the pivoting movement of the locking bar 19. When the front lid 7 is closed, the nose 24 of the front arm 20a of the lock bar 19 is in contact with the lock pin 23. When a cassette is loaded into the video deck, the rear arm 21a of the lock bar 19 is pushed rearward by the activation member 26 to the position shown at 21b. By this,
The front cover 7 is released and can be moved to the open position.

According to the invention, the lock bar 19 has an arm extending beyond the bearing journal 22, i.e.
It is equipped with an arm 25. This third arm 2
5 is the bearing 3 when the front cover 7 is in the closed position.
abutting the wall 27 of the upper part 1 of the cassette, located above 0.

As shown in FIG.
may have an angled shape, in which case the angled portion 25a contacts the rear wall 27 of the upper part 1 of the cassette. The third arm 25 may have other shapes, for example straight or may have a beveled portion at its free end, which beveled portion is attached to the rear wall 27 of the upper part 1 of the cassette. The shape may be such that they touch each other.

This shape of the third arm 25 is similar to that of the bearing 3.
0 to facilitate the insertion of the lock bar 19. The reason is that the third arm 25 can be easily grasped by the assembly tool, for example by sliding the angled portion 25a on the wall 27 and moving the lock bar 19. 19 can be placed at a predetermined position.

After assembling the lock bar 19 into the lower part 2, the front cover 7 and the upper part 1 can be assembled into the lower part 2. This allows the lock pin 23 to be locked when the front cover 7 is in the closed position.
automatically comes into contact with the nose 24 of the front arm 20a.

In FIG. 2, the locked position of the lock bar 19 is shown by a solid line, and the released position is shown by a broken line.

This shape of the locking bar 19 prevents the front arm 20 from moving past the locking pin 23 while the front cover 7 is pivoted from the open position to the closed position, thereby preventing the front arm 20 from moving past the locking pin 23. Front lid 7
prevent accidental opening.

If the locking bar 19 does not have the third arm 25 extending as described above, the locking pin 23 on the side wall of the front cover 7 will be between the two arms 20, 21 of the locking bar 19, and the locking pin 23
However, there is a risk that the locking effect will not be achieved while the front cover 7 is closed.

Furthermore, if the lock pin 23 is under the front arm 20, the lock pin 23 will catch on the end of the rear arm 21 during the opening operation by the starter member 26, and the opening operation will also be hindered.

To provide the force to hold the locking bar 19 in the locked position, a U-shaped leaf spring 28 is used, which is connected to the rear wall of the double side wall 18 which is part of the lower part 2 and to this rear wall. Adjacent lock bar 1
9 and the rear arm 21.

The leaf spring 28 can be made of plastic or metal. This leaf spring 28 is
It is held in place by the rear projection 29 of the rear arm 21. Furthermore, having the third arm 25 shaped as a stop prevents the leaf spring 28 from moving into the free space of the upper part during assembly.

The advantage of a leaf spring designed in this way is that it is simple in shape and easy to manufacture, and that it can be easily inserted through the bottom of the cassette and placed in position after the cassette has been assembled. be.

[Brief explanation of the drawing]

FIG. 1 is a simplified perspective view of a magnetic tape cassette. FIG. 2 is a partial sectional view of a main part of a magnetic tape cassette according to an embodiment of the present invention. 1...Upper part, 2...Lower part, 3...Lower main wall, 4...Upper main wall, 7...Front cover, 8...Outer cover, 9...Inner cover, 11...Hole ,
12...Pivot pin, 19...Lock bar, 2
0...Front arm, 21...Back arm, 2
2...Bearing journal, 23...Lock pin, 2
5...Third arm, 26...Starting member, 27...
...Wall, 28...U-shaped leaf spring, 30...Bearing.

Claims (1)

[Scope of Claims] 1. An upper main wall and a lower main wall each having three side walls, and an opening along the front side through which magnetic tape coming from two reels positioned in plane-parallel relation is fed. a two-part substantially rectangular housing having a substantially rectangular, two-part housing; and a pivoting front lid that partially covers the sidewall and opens and closes the opening, the front lid being in the closed position. It comprises outer and inner covers 8, 9 covering the magnetic tape, the front lid being locked in the closed position by a locking bar which is movable backwards and forwards and which covers the lower part of the cassette. located on one side,
In a magnetic tape cassette for a magnetic recording and reproducing device, the locking bar 19 is located at an acute angle with respect to the first arm 20 that interacts with the pin 23 of the front lid. , a second arm 21 that interacts with the starting member 26, and the lock bar 19 has a bearing journal 22 thereof.
This extending arm 25 extends beyond the
When the front cover is in the closed position, it acts as a stop in contact with the wall 27 of the upper part of the rearwardly located cassette, and the U-shaped leaf spring 28 is connected to the support part 1 of the lock bar.
A magnetic tape cassette characterized in that the magnetic tape cassette is disposed between the rear wall of the magnetic tape 8 and an arm 21 of the lock bar adjacent to the rear wall of the magnetic tape cassette, thereby applying a force to the lock bar. 2. Claim 1, in which a protrusion 29 is provided behind the lock bar adjacent to the leaf spring.
Magnetic tape cassette as described in section. 3. said extending arm 25 of said lock bar;
2. A magnetic tape cassette according to claim 1, wherein said magnetic tape cassette is bent and projects from said upper portion to act as a stopper. 4. A magnetic tape cassette according to claim 1, wherein said extending arm 25 of said lock bar extends linearly and acts as a stopper.